Single Rare-Earth Ions as Atomic-Scale Probes in Ultrascaled Transistors

Continued scaling of semiconductor devices has driven information technology into vastly diverse applications. The performance of ultrascaled transistors is strongly influenced by local electric field and strain. As the size of these devices approaches fundamental limits, it is imperative to develop characterization techniques with nanometer resolution and three-dimensional (3D) mapping capabilities for device optimization. Here, we report on the use of single erbium (Er) ions as atomic probes for the electric field and strain in a silicon ultrascaled transistor. Stark shifts on the Er3+ spectra induced by both the overall electric field and the local charge environment are observed. Changes in strain smaller than 3 × 10–6 are detected, which is around 2 orders of magnitude more sensitive than the standard techniques used in the semiconductor industry. These results open new possibilities for 3D mapping of the local strain and electric field in the channel of ultrascaled transistors.Q.Z. and J.D. acknowledge support from National Key R&D Program of China (Grant 2018YFA0306600), Anhui Initiative in Quantum Information Technologies (AHY050000), and China Postdoctoral Science Foundation (BX201700230, 2017M622001). C.Y. acknowledges support from an ARC Discovery Early Career Researcher Award (Grant DE150100791). This work was supported by the ARC Centre of Excellence for Quantum Computation and Communication Technology (Grant CE170100012) and the Discovery Project (Grant DP150103699)